package C9_7_IntroduceNullObject;

/**
 * @author xugang1
 * @updated 2022/7/25
 * @description 引入Null对象
 */

public class NullCustomer extends Customer{
    public boolean isNull(){
        return true;
    }

    public String getName(){
        return "occupant";
    }

    public String getPlan(){
        return BillingPlan.basic();
    }

    public String getHistory(){
        return PaymentHistory.newNull();
    }
}